Wetting agents are an important part of pesticide and herbicide formulations, as they assure uniform dispersion and proper functioning of the active formulation ingredients. For example, plant surfaces are typically hydrophobic and resist wetting by aqueous sprays, thereby reducing the ability to deposit pesticides and herbicides. For maximum efficacy, wetting of the leaf must be improved by using wetting agents.
Many different products are available for use as wetting agents, in the general classes of anionic, cationic and non-ionic. That there are so many different products available illustrates the diversity of chemistry and tendency for certain surfactant/formulation combinations to be optimum, yielding improved activity as opposed to other surfactants combined with the same formulation. Also, specific interactions of the chosen wetting agent with the selected active ingredients can result in very divergent responses. Determining the best wetting agent can be quite difficult when all interactions are considered.
The selection of an appropriate wetting agent and whether it would be acceptable may turn on the concentration necessary to obtain a certain required wetting effectiveness, and thus the cost for providing the wetting agent in the formulation. Consequently, the search continues for economical wetting agents, usable at low concentrations which provide enhanced pesticide activity via enhanced wetting effectiveness.